There is a circle with a "B" inside it, but no numbers, and what appears to be a proof mark. Both are on the barrel just ahead of the action and behind the rear sight.
The brand name of the rear sight is "Marbles, Gladstone, MI, USA." I did shoot it at the lowest elevation and it hits about 8 inches high at 100 yards with 170 grain SPs, and about 4 inches high with 150 grainers. I plan to try 130s and see if I can get the thing to hit near POA.
